That's a lot of money for a guy who lost six times in two years, and went 8-4 even with arguably the best QB and WR in the country.
Of course, in fairness to A&M, three million per year is a middle-of-the-road salary for SEC coaches these days, and although you can certainly be a bit skeptical of what Sumlin has done to date, I don't think there's any real doubt that he otherwise won't have very serious suitors from other college programs, as well as the NFL. For better or for worse, they had to pay him a very big deal to keep him around, even if he's earned it or not.